Absorption refrigeration system



ABSORPTIdN REFRIGERATION SYSTEM Original Filed Dec. 20, 1935 2 Sheets-Sheet 1 INVENTOR urlis 61 000118 ATTORNEY Dec. 26, .1939. cc. cooNs ABSORPTION REFRIGERATION SYSTEM 2 Sheets-Shee't 2 Original Filed Dec. 20, 1935 W W i its:

' I INVENTOR Curtis 61 Coons ATTO RN EY 35 j should be no close tol erances in its construction.

Patented Dec. 26, 1939 UNITED STATES PATENT OFFICE ABSORPTION REFRIGERATION SYSTEM Curtis 0. Coons, North Canton, Ohio, assignor to The Hoover Company, North Canton, Ohio, a

corporation of Ohio 18 Claims. (Cl. sip-119.5)

This application is a division of my copending application, Serial No. 55,449 filed on December 20, 1935.

This invention relates to continuous absorption refrigerating systems of the household size and more particularly to means for circulating absorption liquid therein.

A common means for circulating absorption liquids in an absorption refrigerating system of the household type in which a refrigerant, an absorbent and an inert gas are present is a vaporlift pump like that disclosed and claimed in anitedwstates Patent to Altenkirch No. ,728,-

In accordance with the present invention, it is proposed to circulate the absorption liquid of such a refrigerating system by means of a power driven pumpof a novel construction and design.

In accordance with the present invention, a centrifugal pump is sealed within the system and the arrangement is such that the amount of circulation of liquid can be controlled independently of the amount of vapor generated in the boiler.

A satisfactory solution circulator for use in a small capacity tightly-sealed absorption system containing an inert gas must be of unusual construction. The ideal pump should not have any valves. It should be cheap to manufacture, capable of operating with a motor which requires but a small amount of power, and have a capacity in the neighborhood of from. one to one and onehalf gallons of liquid per hour. It must be constructed of materials that are not corroded by the fluids in the system and preferably there Accordingly, it is one object of the present invention to devise a pump which will comply with {the specific requirements mentioned above.

It is a particularly important object of this in- ;vention to prevent the presence of any abnormal gas pressure in the pump, a condition which it has been found often occurs in a closed refrigeration system operating over long periods under fluctuating conditions.

Another object of the invention is to incorporate a novel pump in an absorption refrigeration system in a new manner having certain advan- 5 tages to be hereinafter more particularly described.

Still another object of the invention is to prevent a refrigeration system employing an ab: sorption fluid circulator from becoming inoperative due to the presence of a quantity of gas in the circulator.

It is still another object of the invention to provide novel pumping means for the circulation of a liquid and especially to provide a pump which may be hermetically sealed within a closed sys tem.

It is still another object of the invention to provide novel impellers or rotors for small powerdriven pumps,-

It is still another object to provide a novel self-v priming pump'adapted to be used for the purposes set forth.

Other objects and advantages reside in certain novel features of the arrangement and construction of parts and will be apparent from the followingdescription taken in connection with the accompanying drawings, in which- Figure 1 is a diagrammatic representation of a continuous absorption refrigerating system having a pump constructed in accordance with the present invention incorporated therein,

Figure 2 is a vertical cross sectional view of the pump used in the arrangement of Figure 1,

Figure 3 is a transverse cross sectional view of the pumping means shown in the arrangement of Figures 1 and 2, the view being taken on the line 3-3 of Figure 2,

Figure 4 is a perspective view of an impeller or rotor of a liquid pump, the device shown being capable of use in place of the rotor of the pump of Figures 1, 2 and 3,

Figure ,5 is a vertical cross sectional view of another embodiment of the invention, the view showing a pump which may be used'in place of the pump shown in Figure 1, and

Figure 6 is an end view of the pump shown in the arrangement of Figure 5, a portion of the casing being cut away to show the internal construction.

Referring to the drawings in detail, and first to the continuous absorption refrigerating system illustrated in the diagram of Figure 1, it will be seen that the system is shown as consisting of a boiler B, a condenser C, an evaporator E, an

absorber A, and a pump P as essential elements, the e parts being connected by various conduits forming the complete refrigerating system.

The boiler B of the system includes a lower cylindrical chamber ll having a heating tube l2 of known construction at the lower part thereof, and a dome or analyzer portion l3 which is connected to the cylindrical part II. of bafile plates M of suitable construction may be mounted within the analyzer dome l3 to cause gas passing upwardly therethrough to travel in a tortuous path. The gas conduit l5 connects the top of the analyzer chamber l3 to the condenser C. If desired, a rectifier may be incorporated, either in the conduit IE or in the upper part of the analyzer dome IS.

The condenser C may consist merely of a coil of pipe having heat radiating fins thereon, if it is air cooled, a number of such fins being shown at l6. The lower end of the condenser C is connected to the evaporator by means of a conduit IT. The evaporator may consist of a vertically disposed cylindrical vessel having a number of battle plates l6 therein. It is connected to the absorber A by means of two inert gas conduits l9.and 2| which may be in heat exchange relation as illustrated at 22. A drain pipe 23 may also be provided to-drain liquid from the lower part of the evaporator into the absorber.

The absorber may be of any known construction, the one shown in the present arrangement being somewhat like those shown and claimed in through the conduit 2|.

the co-pending application of Coons et al., Serial No. 25,368, filed June '7, 1935.

As shown in Figure 1 the absorber A may consist of a vertically disposed cylindrical vessel having an electric motor 24 mounted on the upper end thereof for driving a shaft 25 which extends longitudinally therethrough. A number of splashing elements or discs 26 are mounted on the shaft in between spaced baflle plates 21 mounted on the cylindrical wall, so that as absorption liquid is supplied "to the upper end of the absorber vessel and flows. downwardly therethrough by gravity, it i s splashed about and thrown around the inside of the vessel by means of the elements 26, the liquid dripping from each baflie plate 21 to the next lower splashing element 26. The upper endi;of the shaft 25 also carries a fan element 28"which discharges into the conduit l9, connected to the upper end of the absorber A. Since the other inert gas conduit 2| is connected to the lower end of the absorber vessel, the fan 28 causes circulation of inert gas from the absorber upwardly through the conduit I9, upwardly through the evaporator E and back to the lower end of the absorber If necessary, additional gas circulators may be employed.

The lower end of the absorber A is connected to the boiler system by means of the U-shaped conduit 29, this conduit being connected to the lower part of the absorber vessel below the point. of connection of the gas conduit 2|, and'to the janalyzer dome l3 above the baffle plates l4 therein. The lower part of the absorber vessel A may actas a reservoir'ffo'r absorption liquid and the quid ieyel nerein ay be such that the liquid will flow by gravityjthrough the pipe 29. The liquid level in the boiler system remains above the baffle plates. l4. A's heat is supplied to the boiler chamber II ,I refrigerant is expelled from the solution supplied through conduit 29. The

weak solution may'fi'owthrough a conduit 30, a

portion of which may be in heat exchange rela- A number conduit 2 lrinto the absorber.

tion with the conduit 29, as illustrated, to the pump P. The pump P has an electric motor 3|, the rotor of which is hermetically sealed within the system in accordance with known construction. The pump causes liquid to flow from the pipe 39, through the conduit 32, to the top of the absorber vessel A.

The pipe 39 may have a portion bent into the form of a coil to provide a pre-cooler for absorption liquid flowing to the absorber.

In case it is desired to by-pass the boiler system and recirculate some absorption liquid through the absorber, a small conduit 33 is connected to the upper left-hand portion of the conduits 29 and 39 (as viewed in Figure 1) and this conduit 33 is provided with a valve 34 so that the amount of liquid recirculated through the absorber may be varied. Additional regulating means may be provided in the form of a valve 35 in the conduit 32.

Since some gases may find their'way into the liquid pump P, and since it is desired to maintain the pressure in the pump casing outside of the rotor chamber the same as that in the absorber, a gas conduit or vent 36 is connected to the pump casing and to the lower portion of the inert gas conduit 2|. The pipe 36 may be provided with a valve as shown at 31.

As shown in Figure l, the location of the pump P with respect to the lower portion of the absorber and the boiler system issuch that the lower portion of the pipe of the pump casing P is at about the same level as the lowerportion or reservoir in the absorber A and is slightly above the point of connection of the conduit 29 with the analyzer chamb'er I3. Under normal operating conditions the liquid level in the pump P, the lowerportion of the absorber, and the analyzer chamber l3 will be about the same, and will be a slight distance above the point of connection of the conduit 39 with the casing.

The only load on the pump, therefore, is that required tolift the absorption liquid from the level in the lower part of its casing to the upper end of the absorber A. In practice this distance may be twelve inches more or less, and in any event the pump needs to lift the liquid only a short distance.

The operation of the system shown in Figure 1 will be apparent to those skilled in the art, the circulation of liquids and gases being in the direction illustrated by the arrows, the liquid circulation being shown in full line arrows while the gas circulation is shown in dotted arrows. Refrigerant gas, such as ammonia, expelled from solution in the boiler B passes upward through the analyzer l3, passing back and forth as directed by the baffles l4 and passing upwardly through the liquid in this analyzer which stands some point above the point of connection of the conduit 29. The refrigerant gas then flows upwardly through the conduit l5 into the con-.

denser C where it is liquified and sentinto the evaporator through the conduit II; In: the evaporatorvthe refrigerant evaporates intothe inertagas, and is conveyed with it through the the refrigerant is absorbed out of the inertgas intoathe absorption liquid and fiows back to'th'e boiler} system through the conduit 29.

At the. same time, the absorption liquid is circulated by means of the pump P,.the liquid fiowingfrom this device upwardly through the conduit 32-.and trickling downwardly over the In the absorber.-

baflle plates2'l and splashing-element 26 in the absorber so that it comes in intimate contact with the inert gas and the refrigerant gas as it flows downwardly therethrough. The absorption liquid which is not recirculated through the pump by conduit 33, flows through the conduit 29 into the boiler system and from there back to the pump P through the conduit 30.

The pump P may, of course, take various forms and one form is shown in detail in Figures 2 and 3. The pump includes a cylindrical housing or main pump casing 38 to which end plates 39 and 40 are bolted by means of bolts 48 and 42 which are screw threaded into flanges 55 on the main part of the casing 38. The pump casing must be suificiently strong to withstand high pressure and the end plates 39 and 55 must be sealed to the main casing 38. Suitable sealing means such as the gaskets 44 may be provided, as illustrated. The end plate 39 is merely a sealing means which provides a chamber 45 on the right-hand portion of the assembly, as viewed in Figure 2. The liquid inlet pipe 30 is connected to the lower end of the chamber 45 and the gas vent pipe 36 is connected at the upper end. It will be understood that the liquid normally stands at a level in the lower portion of this chamber 45 and that the upper portion of this chamber is at the same pressure as that in the inert gas conduit 2i and the upper portion of the absorber, except 1 for slight differences due to movement of the The left-hand end plate 40, as viewed in Figure 2, has a central opening 45 therein, surrounded by a flange 41 to which the housing of the sealed motor is secured, the housing being shown at 48 and the bolts for securing it to the flange 41 being shown at 49.

The electric motor 3! has its rotor (not shown) mounted on the shaft 50 which extends horizontally through the casing 38 so as to enable the motor to drive the rotor of the pump. Located within the main pump casing 38 is an inner rotor chamber or casing within a casing. Two complementary housing members 59 and 52 are secured by means ofbolts 53to each other and to an inwardly extending flange 54 on the outer casing member 38which holds the members 56 and 52 apart. The members 58 and 52 carry bearings 55 for the shaft 50 and they cooperate with the inwardly extending flange 54 in such a way as to provide a space therebetween for the rotor 56 mounted upon the shaft 55.

The construction of the rotor 56 is best shown in Figure 3. The form there shown consists of a disc having its periphery provided with a number of teeth 51. Each tooth preferably has a forward portion out upon a radius of the disc and a rear portion out along a chord thereof so as to provide a sort of right triangular shaped pocket in advance of each tooth. Liquid is supplied to the inner pump casing or chamber in which the rotor 56 is mounted by means of an opening 58 in the lower portion of the inner housing member 52. Ah unusual feature of this pump results from-the location of this inlet to the rotor chamber.

As is well known, a centrifugal pump comprises an impeller rotating inside a casing. In usual constructions the liquid enters the pump close to the center of the impeller and is given a circulatory motion as it is forced outward due to centrifugal force. Considerable hydraulic pressure can be built up at the periphery of a rotating impeller.

The volumetric efliciency of. centrifugal pumps depends partly upon the capacity of the pump. As the size of the pump is decreased, the pump becomes less efiicient. Besides a loss due to back leakage, other losses occur from friction between the impeller and the liquid and from shock of the liquid inside the pump and these losses are relatively larger in a small pump than in a large pump.

In so far as centrifugal pumps of usual design are concerned, the circulation of a liquid at a rate of only one or two gallons per hour, and lifting it against a head of only a few inches involves the design of a very small pump. In order to lessen the losses mentioned above due to skin friction, liquid shock etc., it has been found that the efficiency is materially increased if the inlet 58 to the rotor chamber is a considerable distance away from the center of the rotor 56, and that for the peculiar requirements for which the present pump has been devised, the inlet to the rotor casing may be only a fraction of an inch away from the periphery of the rotor.

While only one opening 55 has been shown in thearrangements of Figures 2 and 3, it has also been found that the pump operates satisfactorily if several openings are provided in the inner casing member 52, the openings being spaced circumferentially along the lower portion thereof.

The various parts of the pump construction of Figures 2 and 3 may be made of stainless steel, although it is of some advantage to employ lighter metals. In one pump which has been construct ed, satisfactory results have been obtained with the members 56 and 52 as well as the rotor 55 constructed of aluminum. In this construction the bearings 55 were constructed of rubber and were lubricated by ammonia solution in the pump casing.

In 'order to provide communication between the chamber in which the rotor 55 of thepump is mounted and the outlet supply conduit 52 a hole may be drilled in the flange 55 of the outer casing 38 and the pipe 32 welded to the casing 55 at this point. As shown in Figure 3, the hole 59 is tangentially arranged with respect to the periphery of the rotor 55 and is spaced from inlet 55 only about 90 degrees. Thus the liquid which enters the chamber through the opening 58 travels only a short distance under the influence of the impeller 55 (rotating in the direction of the arrow shown in Figure 3) before it leaves the pump casing through the opening 59. The

frictional loss with this construction is thus less eter of 3 inches. The other parts of the pump in these figures are drawn approximately to scale.

It will thus be seen that, as centrifugal pumps go, it is very small. With such a small size pump, the capacity is very sensitive to a change in liquid head at the inlet 58. This difllculty. is overcome in the present invention, at least to a large extent, by maintaining the liquid level in the pump chamber 45 nearly constant. This can. be done if the pipes 29 and 30 are of fairly large diameter, so that the level in the chamber 45 is always about the same as that in the reservoir in the lower part of the absorber. It will be understood, of course, that in order for liquid to flow from the reservoir through the boiler and into the pump, the level in the reservoir will have to be slightly higher, but if the pipes 29 and 30 are fairly large, this diii'erence will be small.

The maintenance of a constant level in the chamber is facilitated by means of the pipe 36 which prevents changes in pressure which sometimes occur in various parts of a refrigerating system for one reason or another, from causing liquid to flow fromone part to another. With an arrangement constructed as illustrated, the level of liquid in the chamber 45 remains practically constant, and so long as the speed of the rotor remains constant, the quantity of liquid pumped per unit of time remains'substantially uniform. I

The rotor 56 of the arrangement of Figures 2 and 3 may not be of exactly the form shown but may have a wide variety of shapes and constructions. Figure 4 shows a small aluminum disc 6| which may be usedas an impeller in the pump of Figures 2 and 3 in place of the impeller 56. The disc 6| is provided with six vanes or impeller elements 62 attached to each side thereof and equally spaced circumferentially thereon.

In the arrangement shown, with the disc in the neighborhood of four inches in diameter, the vanes may be one-half inch long and stand out one-sixteenth inch on each side of the surface of the disc. The clearance between the periphery of the rotor and thecase should be about onesixteenth inch.

Still another embodiment of the invention is shown in Figures 5 and 6. In this construction the pump casing comprises two complementary parts 63 and 64, the part 63 having a flange 65 thereon to which the housing 48 of the motor is connected as in the arrangement of Figure 2. The part 64 is cup-shaped and is secured to the part 63 by bolts 66. A shaft driven by the electric motor, as in the arrangement of Figure 2, carries a disc 61 which has a curled flange'68. The inlet liquid supply conduit 30 passes through the cup-shaped casing member 64 and ends at apoint just inside the lower portion of the curled flange 68 of the disc 61 so that liquid flowing through this pipe falls upon the inside of the flange. As the disc 61 is rotated, the liquid clings to the inside of the flange 68 and iscar- -ried away from the upper part of the flange 68 through a pipe 69 which is arranged tangentially therewith, as best shown in Figure 6. The liquid remains within the inside of the curled flange 68 due to centrifugal force. A gas vent pipe 36 like that in the arrangement of Figure 2 is connected to the chamber 10 around the disc 6'! so as to maintain the pressure in this chamber the same as that in the absorber.

With.this construction, some liquid may spill over around the curved flange 68 or be carried with it on the outside up into the upper part of the chamber 10. To remove this liquid 2. pipe-1| connects the upper part of the chamber 10 to the inlet pipe 30. This pipe drains away any liquids carried to the upper part of the chamber outside the flange of the rotor 61. During normal operation of the arrangement of Figures 5 and 6 the disc 61 should not dip into liquid, for if it does considerable drag on the rotor results. For. reasons mentioned above, in a small sized pump, this drag is important.

The'shaft 50 of the arrangement of Figure 5" may be supported in part by a rubber bearing 12 held in place by a supporting disc 13 secured to the motor housing 48. The disc 13 has a hole M therein for preventing liquid from collecting in themotor housing.

Assuming that the pump of the arrangement of Figures 5 and 6 is connected into a refrigerating system so that it occupies the same place that the pump P occupies in Figure 1, then, when the disc 61 stops rotating some liquid will flow from the reservoir of the absorber into the chamber 10.

When the pump starts up again this liquid will be carried by the disc 61 up to the point of connection of the pipe H and then flow back to the inlet pipe 30. The liquid on the inside of the curled flange 68 of the disc will flow away through the outlet 69 and the pipe 32 back to the absorber. As the disc 61 continues to rotate the pool of liquid will be removed from the lower part of the chamber HI and there will no longer be any appreciable drag upon the rotation of the disc 6].

Pumps constructed in accordance with the present invention may be used inseveral diiferent kinds of absorption refrigerators. In my copending application Serial No. 49,444, filed November 13, 1935, a pump like that claimed herein is used in a system having a compound boiler.

While only a few embodiments of the invention have been shown and described herein, it is obvious that various changes may be made without departing from the spirit of the invention or the scope of the annexed claims.

I claim:

1. A liquid pump connected into a tightly sealed system and operable to transfer a liquid from'one elevation to a higherelevation therein, said pump I comprising a chamber having an upstanding rotary impeller therein, the lower portion of said impeller being normally submerged in the liquid at said lower level, a gas chamber within said pump above said liquid, electro-magnetic drive means for said pump sealed within said chamber,

and means for preventing pressure fluctuations in the system from disturbing the liquid level in said pump.

2. A tightly sealed continuous absorption refrigeration system containing fluids in. both the liquid and gaseous phase, a pump operable to raise the liquid from one level to a higher level in the system comprising a casing, a second casing within said first casing and communicating therewith, a rotary impeller within the second casing, the liquid level being normally above said I communication opening but below the toptof the second casing, and means for preventing pressure fluctuations in the system from disturbing the liquid level in said pump.

3. A tightly sealed continuous absorption refrigeration system containing fluids in both the liquid and gaseous phase, a tightly sealed electromagnetically driven pump operable to raise the liquid from one level to a higher level in the system, said pump comprising an outer casing and an inner casing communicating therewith, said inner casing housing a rotary impeller, which dips into the liquid at the lower level, and means connecting the outer chamber above the liquid to the space above the source of supply whereby accumulations of gas in said chamber may be drained, and pressure fluctuations in the system will not afiect the liquid level in said outer chamber.

4. A continuous absorption refrigeration system containing fluids in both the liquid and gaseous phase and including a boiler and an absorb'er having a portion above the boiler, a tightly sealed .electro-magneticallydriven pump operable absorber, said pump including an inner chamber and an outer chamber, a rotary disc impeller in said inner chamber, having peripheral means operable to lift a liquid from .a lower level to a higher level, a liquid supply adjacent the periphery of the disc, peripheral discharge means located a short distance above said inlet and connected to the upper portion of the absorber, and means interconnecting the pump inlet chamber and the absorber to equalize the pressure therein.

5. A continuous absorption refrigeration system comprising a boiler, a condenser, an evaporator and an absorber, means connecting the same in circuit, said system having a refrigerant, an absorption medium and a pressure equalizing medium therein, said connecting means providing a refrigerant circuit, a pressure equalizing circuit between the absorber and evaporator, and an absorption medium circuit between the boiler and absorber, a circulating device of the centrifugal type sealed in said absorption medium circuit for circulating said absorption medium, and a pressure equalizing connection between said circulating device and said pressure equalizing medium circuit.

6. A continuous absorption refrigeration system comprising a boiler, a condenser, an evaporator and an absorber, said system being of the type employing a refrigerant, a pressure equalizing medium and an absorption medium, means providing a circuit for the refrigerant, a pressure equalizing medium circuit between the evaporator and the absorber, and an absorption medium circuit between the boiler and absorber, electromagnetically driven means of the centrifugal type in said last named circuit, and means for I preventing the total pressure in said device from rising appreciably above that in said equalizing medium circuit.

'7. A continuous absorption refrigeration system comprising a boiler, a condenser, an evaporator and an absorber, said system being of the type employing a refrigerant, a pressure equalizing medium and an absorption medium, means providing a circuit for the refrigerant, a pressure equalizing medium circuit between the evaporator and the absorber, and an absorption medium circuit between the boiler and absorber, electromagnetically driven means of the centrifugal type in said last named circuit, and means extending between said pressure equalizing circuit and the space between the inlet and discharge of said device to. prevent the total pressure in said device from rising appreciablyabove that in the last named circuit.

8. A liquid pump for use in a closed system containing a gas and a liquid comprising an outer casing and an inner casing, an electro-magnetically driven impeller disk within the inner casing, said inner and outer casings being in communication, a liquid supply opening in the outer casing, and a liquid discharge opening in the inner casing, and means adapted to provide communication between the upper part of the outer casing and a part of the system included in the liquid circuit containing the pump to prevent pressure fluctuations therein from disturbing the liquid level in the pump.

9. A fluid pump for use in a closed system comprising an outer casing and an inner casing communicating therewith, means including an elec-' tro-magnetically driven impeller device within the inner casing, said inner casing having an oil-less bearing lubricated by the fluid being pumped supporting the impeller, and the outer casing supporting the electro-magnetic means, fluid supply means for said outer casing and fluid discharge means for said inner casing.

10. A fluid pump for use in a closed system comprising communicating inner and outer casings, a rotary impeller disk in the inner casing, oil-less bearing means supporting said disk, driving means for the disk secured to the outer casing, fluid supply means near the periphery of the disk, and fluid discharge means in the inner casing and removed only a short circumferential distance from said supply means, said disk having means extending radially thereof for imparting movement to the fluid through said discharge.

11. In a continuous absorption refrigeration system of the type employing a refrigerant, an

absorption fluid, and a pressure equalizing medium and including a boiler, condenser, evaporator and absorber connected in a closed circuit, said system being characterized by having an absorption fluid circulating device'therein in the boilerabsorber circuit, an electric motor for driving said fluid circulating device sealed within said system, said device having an upstanding rotary impeller, the lower portion of which is normally submerged in the absorption fluid, and a pressure equalizing connection between the space above said level in the pump and the absorber whereby pressure fluctuations in the system will not disturb said fluid level.

12. In a continuous absorption refrigeration system of the type employing a refrigerant, an absorption fluid, and a pressure equalizing medium and including a boiler, condenser, evaporator and absorber connected in a closed circuit, said system being characterized by having an absorption fluid circulating device therein in the boiler-absorber circuit, said device comprising an inner casing and an outer casing surrounding the same and. communicating therewith, an electro-magnetically driven impeller in the inner casing, a liquid supply to the outer casing, and a liquid discharge for the inner casing, and a pressure equalizing connection between said outer casing and said closed circuit whereby pressure fluctuations in said system will not disturb the operation of said circulating device.

13. In a continuous absorption refrigeration system of the type employing a refrigerant, an

absorption fluid, and a pressure equalizing medi' um and including a'boiler, a condenser, an evaporator and an absorber connected in a closed circuit, said systembeing characterized by having an absorption fluid circulating device therein in the boiler-absorber circuit, said device comprising a casing, a rotary member in the casing mounted in oil-less bearing means and driven by electro-magnetic means sealed to said casing, said member having a circular flange thereon, means delivering absorption fluid to the lower portions of said flange, means positioned to pick up the fluid carried,to the upper portions of said flange when said member is rotated rapidly, and means providing communication between the upper portion of said casing and said system to prevent pressure fluctuations within the system from interfering with fluid flow to or from said circulating device. I

.14. A continuous absorption refrigeration systememploying fluids in both the liquid and gaseous phase and including a boiler and absorber in circuit, a device in said circuit operable to circulate a liquid-therethrough, comprising a casing having an inlet and an outlet, an electroto circulate a liquid therethrough, comprising a casing, an electro-magnetic motor supported by said casing having a shaft journaled in an oil-less,

bearing, a rotor on said shaft having a curled flange, means delivering liquid to one portion of said flange, means positioned to receive liquid from said flange when the rotor is actuated and convey the liquid to a higher elevation in said circuit than said delivery means, and means positioned to collect liquid overflowing from said flange and convey the same back into the main liquid stream whereby the only liquid normally in the casing is that carried by said rotor.

16. A continuous absorption refrigeration system employing fluids in both the liquid and gaseous phase and including a boiler and an absorber in circuit, a liquid circulating device in said circuit comprising a casing, a power actuated, flanged rotor in said casing, means delivering liquid to one part of said rotor, and means positioned to discharge liquid from another part thereof when the rotor is actuated, and means operable to return surplus liquid from said casing into the main liquid stream.

17. A continuous absorption refrigeration system employing fluids in both the liquid and gaseous phase and including a boiler, and an absorber in circuit, a liquid circulating device in said circuit comprising a casing, a power actuated, flanged rotor in said casing, means delivering liquid to one part of said rotor, means positioned to discharge liquid from another part thereof when the rotor is actuated, means operable to return surplus liquid from said casing to the'main stream, and means connecting said casing with a part of the system containing a gas whereby fluctuations in pressure in the system will not interfere with the operation of said circulating device.

18. A liquid pump comprising a casing, a power driven, flanged rotor therein, a conduit to deliver a liquid to the lowerpart of the rotor, means positioned to convey liquid away from the upper part of the rotor, and means for returning liquid overflowing from the rotor into the casing back to the rotor to be discharged from said casing.

CURTIS COONS. 

